Genesis 17:9-11

9And God said to Abraham, “As for you, you shall keep my covenant, you and your offspring after you throughout their generations. 10This is my covenant, which you shall keep, between me and you and your offspring after you: Every male among you shall be circumcised. 11You shall be circumcised in the flesh of your foreskins, and it shall be a asign of the covenant between me and you.
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